Improvement in dental articulators



work. "Eirst,my,inventionconsists asupportingy 'stock, carrying. ajsliding rod to the upper end y of which ispivoted :agmo'vablefsocke t,jin comfbinationjwith a slidingVv rod earryingfthe i model-l1oldersl,' andy provided with Va ball ylit,- *ting Vin the,V swinging .,Jsoclret,aslhereinater Uma-STATES PATENT EEroE.

l GEORGE ,'G. DAvIDsoN, or LAMBETH, GREAT BRITAIN,-

-IMPRovEMENT IN DENTAL ARTICULATQRS.

Specificationforming part of Letters Patent No. 175,046, dated March 21, 1876; appliction Vfiled February 17, 1876.

. dentaloperator ma'ylx the castsor models of a"patien`ts jaws ina position corresponding to that ofthe jaws-themselves, `and having done Y so, turnl orlrevolve theseirnodels inevery posi sible direction, yalso remove the holders'of the models fromfltheinstrument and replace them @tally weleer-in anrdiretioereqifed sv t0 enable the ,modelsf mounted v` onjthe `holders to beiworked,upon lbyanyoperator infthegab `gsenceofthe,patient;and the whole of the dentists workto beaeconplished with greater facility than :bytanyef thefmethousat ,present useof@fitting` articiahteethito models;

` #tartsorzolgasslid thelthleipf them being j y so. arranged; as to enable theoperatorto place -lq thetwormodels-in anygcorrelative position to fone-a other thatnmay required `fondental more fully set fort v `Second,"inffthcjfco binationwithfthe stock providedwithphor ontalzand vertical tubes,l i the lattertubesbe V lugs and adjusti g-so'iew's, of the slidingrod, provided withfagfswingin g v socket, 1 andthe i rod carrying the model holders, and providedv with a ball iitting` .in"sai d socket and a n ut l providedwithsuitable for eo'nning the ball in position, as hereing after set forth.

"Inthe accompanying drawings, Figure 1 is I a longitudinal section 'ofv myimproved dental articulator, furnished with a e ball-and-socket "`l joint'.` Fig. 2 isan' e nd view of the same.

of Denta-l Articulatorsof which thel suspender G.

.Fig 3 is a plan of the same apparatus, showing the upper model-holder, and Fig. 4 a sectional plan, showing the lower modelgholder. Fig. 5 is a longitudinal section' of' a hingejoint, equivalent to the ball-andlsocket joint, Figs. 1 to 3. Figs. 6, 7, and 8,9 are elevations and plans of the upper and lower modelholders, respectively, in a modified configuration.

In Figs. 1, 2, 3, and 4, A is the stock or stand consisting of two tubes, placed at right angles to one another. The vertical tube B I furnish with two lips of lugs, b, separated from each other by a' slit, d, andfwhich may be brought close to one anotherby means of a thumb-screw or similar appliance, D.: Within this tube there is a rod, E, surmoujnted by a head-piece, F, and which Ymay beftixed at any height by means of thebindingscrew D. G is the holder or suspender forl thejmodel of the upper jaw. It is furnished with a tube, H, having a pair of lips, b b', a `sl it,d, and a binding-screw, D', toit, like theitbeB. This tubel slides upon a rod, I, audits position is "adjustable by means of the screw ID'. The rod I ends in a ball, J, held withina socket, K,

`furnished with a fork, L L, fitted to'vthe head A F of the rod E, upon whichthejwhole socket is thus suspended by means' "the axis N, the ball itself being adjusted ,inl ,the position required within the socket by means of the female screwM. l

j y The holder O of the model offthelower jaw is similar to the top model-holderor` suspender IG, `but furnished with a rod, I `s` l iding within v thehorizfontal tube C ofthe st .orstand A. .Toenable the holder O to hf v Aongitudinal sliding motion imparted to it, .and'to beiixed in any desired position, it is furnished'w'ith a pair of lips, b2, and a bindingscrew,'l)2like the Instead of .theifsuspender Gr being furnished with a tube andslidi'ngupon a rod, it may have a rod to it sliding vwithin a tube ending in the ball J and` similarly, by way of interchange, the lower model-holder may have a tube to it and slidefupon a rod,

instead of having a-rod attached `to it which slides within the tube G.

VBy the arrangement just deseribed it will be seen'that each of the organs of my improved dental articulator has'avmovemvent of its own. The suspender G, with the upper model fitted to it, may slide to and fro on the rod I and also rotate or gyrate, so that it may be placed at any angle to the vertical plane passing through the axis of the rod I. The rod I may vary its positions indefinitely by virtue of the ball-and-socket arrangement J K. The socket K may describe any aro around the axis N on which it is suspended, and to the vertical rod E to which the fork L of the socket K is fitted, both a longitudinal and an angular motion may be imparted, in the same manner as to the suspender G., The same duplex motion may be given to the lower model holdei` O, sliding within the tube C and adjustable at any angle. In this manner any one point ot' either of the two models may have its co-ordinates varied indelinitely.

Both model-holders, G and O, being separable from the stock or stand A and from the rest ot' the instrument, the models, mounted thereon and held together by means of Wax or other agglutinating material, may be readily transferred to another instrument, and

thus the same apparatus may do service for several fresh sets ot' models without the old ones being taken ott their holders. For the rod E (shown in Fig. l) another of greater length maybe substituted, so as to become applicable to di'erent heights of models, as

made by diierent dentists.

Forthe ball-.and-socket arrangement shown in Figs. 1, 2, 3, any description' of mechanism may be substituted by means of which an analogous combination of movements is achieved. Fig. 5 shows a longitudinal secti'on of a hinge-joint exemplifyingthese mechanisms. Upon the head F of the rod E a fork-piece, L, is mounted in the same way as in Fig. l. To this fork-piece an eye, Q, is titted,carrying a fork, R, on which thc-rod I,

' Fig. 1, or an equivalent tube, S, may be susy pended. In thiscase the rod I or the tube S |noyes up and down aroundthe center 'l ot' the fork-piece It, which rotates or gyrates ,""horizontally around its axis U, secured by means of a set-screw, D3, and forming likewise the center of the eye or lug, Q, which may be moved up and down like the rod I or the versa, may not appear essential, and where it "may be expedient to sacrifice this feature tor the advantage of being able to Iix the organs l at once inthe position required, I substitute prismatic bars for the rods shown in Figs. 1

the model-holders in their proper places without any extra appliance.

For the circular form of the model-holders, Figs. 3, 4, a longitudinale-that is to say, cy-

lindrical, prismatical-or other suitable form,

may be substituted. A longitudinal section and a plan of an upper model-holder of this kind are shown in Figs. 6 and 7, respectively, and ot' a lower model-holder in Figs. 8 and 9, respectively. In both cases the body of the model-holder is so formed4 that the models may be cast thereon directly. A setscrew, W, is also provided, around which the molded material gathers. and which,`being withdrawn by means of a screw-driver or key, allows ot the model being removed from the holder and another substituted in its place. These model-holders may also betted with rods or with tubes ad libztum, andin combination with them prismatic bars andcorresponding tubes may likewise be used, as well as racks and pinions, worm-wheels and screws, or analogous appliances.

Having thus describedA my invention, I wish to be understood that what"` I claim as new, and desire to secure by Letters Patent, is-

1. The combination of the` stock A, the sliding rod E, the socket/j K1 'pivoted on the sliding rod I, having a ball,J, fitting, in the socket K, and the model-holders G and '0, all substantially as and fort'he object specified.

2. The combination of.' the stock A, provided with the horizontal tube() and vertical tube B, having the lugs yb andadjusting-screw D passing through the same,"wi`ththe sliding rod E havin'gthe head F, the socket K piv oted in said head, the4 rod Ihaving a ball {itting the socket K, the-nutM' confining the ball in place, and the'model-holders G and 0, all substantially as described.

GEORGE GENESE DAVIDSON.

Witnesses: y y

J. T. DANN, i

l OrawshayRoa,*LBrton S. W. SAMUEL OHALLEN 'GREENFIELD,

59 Treheme Roa@ Brixton S. W. 

